Switch heating device



May 8, 1934. E. R. PACKER I SWITCH HEATING DEVICE 2 Sheets-Sheet l Filed OCc. 2l. 1930 ATTORNEY May 8, 1934. E, R, PACKER SWITCH HEATING DEVICE Filed Oct. 2l, 1950 2 Sheets- Sheet 2 I WT u @yr/2f /w 2a ff@ ATTORNEY Patented May 8, 1934 UNITED STATES PATENT FFCE 6 Claims.

This invention relates to the art of protecting railway switches, movable point frogs and similarv railway devices from interruption to their proper operation by the accumulation of snow and ice under severe weather conditions and consists of an improved construction and arrangement of electrical heating devices particularly adapted for obtaining a high degree of efficiency in installations of this character, and which moreover are capable of being readily and inexpensively installed in Varied spaced relation to accommodate the installation to the variations of tie spacing as encountered in diiierent switch structures.

Aparticular object of the present improvements is to provide an improved heating device comprising the advantages of the so-called contact type of heating unit with that of the radiation type of heating unit, as heretofore employed. The former, i. e., the contact type of heater, as heretofore employed, consists of a heating unit secured to the track rail immediately adjacent to the movable switch point and in con tact with the rail so as to heat the rail by direct conduction of the heat thereto from the unit. This type of heater, as heretofore employed, is advantageous in preventingd accumulation of snow against the otherwise cooler rail surface but has been deficient in the protection of the space between the rail and movable point, particularly under certain wind conditions; the latter type, or radiation heaters, as have been employed, consist of heating units placed between the. ties and beneath the switching space to be protected and without direct contact with the rails. This latter type offers the advantage of better heating of the space between the rail and movable point together with heating of the bailast to give proper drainage, but wherein the heating of the rail is effected indirectly by radiation from the heating units and the rising of heated air and accordingly for successful operation under .severe conditions requires units of relatively large current consumption. In accordance with the present invention there is provided an improved heating unit designed for at'- tachment to the fixed track rail with a suitable area of direct contact therewith to accomplish the heating of the rail by direct conduction from the unit and having the body of the heater unit extended inwardly to underlie the movable switch point and switching space to be protected. This improved arrangement accordingly provides electric heating units operative to offer adequate protection to the switching space likewise to effect heating of the rail with a materially reduced current consumption over the types of heaters referred to.

Other important features of the present invention include an improved heater unit con- 50 struction employing a highly eicient resistance element with provision for enlarged radiating surface areas; provision for conveniently replacing of the resistance elements when required, economy of manufacture and simplied means G5 for attaching the heater units to the rail with security against displacement from the track vibration.

rThe foregoing and other desirable features and advantages of my improved construction will be more fully understood by reference to the accompanying drawings wherein like reference characters are applied to the corresponding parts in the several views.

In the drawings:

Fig. l is a plan view of my improved heater unit construction.

Fig. 2 is a view in vertical transverse section through the rail showincr my improved heater unit attached thereto and in side elevation.

Fig. 3 is a detailed cross sectional View through the heater unit on line 3 3 of Fig. 1.

Fig. is a similar View taken on line 4 4 of Fig. 1.

Fig. 5 is a plan view of a typical installation showing the arrangement of my improved heatunits in connection therewith.

Fig. 6 is a plan view of a modified construction having other means for attaching the device in position.

Fig, 7 illustrates the structure substantially similar to Fig. l, but wherein the heating element is of different form to obtain increased heating effect by conduction to the rail.

Fig. 3 is a detailed cross sectional view thereof taken on line 8-8 of Fig. 7.

Fig. 9 is a side elevation showing a further modified form.

In accordance with my present invention I desirably employ portable electrical heating units of a standardized size and capacity wherein the heating eieinents are tightly sealed in manufacture and the units containing the heating elements are adapted to be variously spaced or distributed, as allowed by the tie spacings of a given switch installation and the units are electrically connected in multiple or series as required, to proportion the resistance value with relation to the voltage of the service available at the location of their use.

The electrical resistance heating elements of the units are desirably composed of a length of metal tubing within which is encloseda coil of resistance wire extending lengthwise therethrough and insulated from the tube by means of a suitable insulating powder, the tube being sealed at its ends and provided at its extremities with suitable insulated terminal extensions 0r binding posts for the connection of electrical conductors thereto. These resistance elements indicated at l are, in my improved device, clamped in position between the upper and lower heater unit sections 2 and 3 formed of cast metal of a suitable size to be received between railway ties of normal spacing. rlhe heater unit sections are designed to form a casing to support and protect the resistance elements and to provide an enlarged radiating surface for more effective distribution of the heat radiation.

As best shown in Figs. 4 and 5, the lower section 3 of the unit is desirably in the form of a flat plate, while the upper section 2 thereof is formed with marginal depending flanges 4 to enclose the lower plate and is further formed with depending flanges 6 to provide a suitable socket or groove to enclose or embrace the resistance elements which are clamped therein by means of the screw studs 8 passing through the sections and secured by nuts 9 at the under side, as shown. The groove for receiving the resistance element, as shown in the structure of Figs. 1 to 5 is formed to parallel the longer side walls of the unit with a reverse bend at the inner end and at its outer end the casting of the upper section is formed with suitable sockets 10 for enclosing the terminal connections to the resistance elements from the leads or conductor wires. For securing the heating unit in position to the under side of the track rail section, the upper unit section is provided on its upper surface with opposite shoulders 14-l4 adapted to engage the inner edge of the rail ilange and at the outer side is formed with an upward bracket extension 16 formed to freely overlie the rail base flange and provided at its upper inward end with threaded apertures for the reception of set screws 18 tted with locking nuts 19. The spacing of the bracket 16 from the rail section, as will be readily understood, allows of clamping of the unit by means of the set screw to rail sections of varied sizes.

The section 2 of the heating unit between the shoulder 14 and bracket 16 is formed with a flattened rail seat portion for contact engagement with the under surface of the rail base flange to provide for direct conductivity of the heat from the heating unit to the rail.

In further accordance with the present invention the heating unit is elongated to provide a portion 20 inwardly extending from the rail between the tie and iuiderlying the movable switch point and the switching space between the movable rail or point and the Xed track rail which, as is readily appreciated, is the critical space where protection is required against the accumulation of snow and ice. The inward extension of the heating unit accordingly provides for effective heating of the switching space by radiation and rising of the heated air while the contact area from the rail provides for its heating by direct conduction with the heater to insure against snow and ice adhering to the rail. The improved arrangement accordingly effects a materially improved distribution of the heat, allowing greater heating efficiency with relatively reduced current consumption. .i

The manner of installing my improved heaters is shown in Fig. l in connection with a typical switch installation and wherein, as shown, the improved heater units are attached to the under side of the running rail in position between the ties, as the conditions will allow, and the units are then connected up in series by conductors or leads 21 in plural number to give the resistance value suited to the circuit available at the specific location.

In Fig. 6 I have shown a suitable modied construction of my improved heater unit, conforming generally to that hereinbefore described, but wherein the lug and bracket of the iirst described construction is omitted and in place thereof the uppermost unit section is formed with laterally extended perforated ears or lugs 25 adapted to be secured to the upper edge of a tie for securing the unit in position in conjunction with a hook shoulder 26 integrally formed on the upper surface of the upper unit section and adapted to closely overlie the rail iiange.

In Figs. 7 and 8 I have shown a further desirable modiflcation of design for obtaining an increase in the ratio of the heat conducted to the rail section, structurally conforming to that rst described, with an altered contour of the resistance element groove, wherein, as shown, the resistance element is formed of connected double reverse loops to give additional heat generation beneath the rail section.

In Fig. 9 there is shown a further desirable modification conforming to the construction as first described, but wherein the portion of the heating unit inwardly extending from the fixed rail, is inwardly and downwardly inclined to bring the heating effect into closer contact with the ballast to insure better drainage conditions and further to give clearance and a deiiecting surface for foreign objects which might possibly tend to lodge within the switching space.

Having described my invention, I claim:

l. A heating unit for railway switches and the like comprising an electrical resistance element and a protective casing therefor adapted for clamping to the underside of the rail base between the ties, said casing being formed of upper and lower separable plate sections formed for clamping of the resistance element therebetween, said upper section being provided with securing means for attaching the unit to the rail with a suitable area of contact with the underside of the rail base for heating of the rail by conduction and with a portion of the unit extended inwardly to underlie the switching space between the ties, substantially as described.

2. A heating unit for railway switches and the like comprising an electrical resistance element and a protective casing therefor adapted for clamping to the underside of the rail base between the ties, said casing being formed on its upper surface with a shoulder for engagement with the inner edge of the rail flange and with a bracket formed to overlie the outer rail flange and a set screw carried by the bracket to engage the rail for rigidly securing the unit in positon.

3. A heating unit for railway switches and the like comprising an electrical resistance element and a protective casing therefor adapted for clamping to the underside of the rail base between the ties, said casing being formed of upper and lower separable plate sections formed for clamping of the resistance element therebetween, said upper section being formed with shoulder means for engagement with the inner side of the rail flange and with a bracket extension formed to overlie the opposite rail flange, a set screw carried by the bracket to engage the rail for securing the unit thereto and said securing means being positioned to secure the unit with a suitable area in contact with the underside of the rail base portion and with a portion thereof extended inwardly to underlie the switching space between the ties, substantially as described.

4. A heating unit for railway switches and the like comprising an electrical resistance element and a protective and heat radiating casing therefor adapted for clamping to the underside of the rail base between the ties, said casing being formed of separable sections for clamping of the resistance element therebetween, one of said sections being formed with flanges on its inner surface forming a groove with reverse bends to position the resistance element, means for clamping the sections together and means for securing the unit to a rail.

5. A heating unit for railway switches and the like comprising an electric resistance element and a protective and heat radiating casing therefor adapted for clamping to the underside of the rail base between the ties, said casing being formed for attachment to the rail with a suitable area in contact with the rail for heating the latter by conduction and having a portion inwardly extended to underlie the switching space between the ties, said latter portion being downwardly and inwardly inclined and means for securing the casing to the rail.

6. A heating unit for railway switches comprising an electric resistance element and a protective casing therefor, said casing being formed for attachment to the rail between the ties and to position the resistance element to immediately underlie the rail for heating of the latter by conduction and with a portion inwardly extended to underlie the switching space between the ties and means for clamping the unit to the rail.

EBEN RAY PACKER. 

